Preventing Window Collisions

Today, birds are constantly facing various threats to their survival, both in the air and on the ground. A fatal obstacle that most people do not consider is collision with reflective windows. Window collisions are considered by ornithologists (those who study birds) to be the second largest cause of mortality after habitat loss, causing millions of deaths just in the United States.

Most of the deaths from collisions with windows occurs during the spring and fall migration season. Essentially migrating birds cannot distinguish the reflection as a window and they think they can fly through it. Something can be done – one simply needs to break up the reflection every 4 inches.

What you see are treatments placed on windows on a building in Veterans Park, Gainesville, FL. Called Acopian Birdsavers, these treatments are paracord that is strung every 4 inches. Birds see these as significant barriers and will not fly into windows.










Anybody can build these! Materials are heavy duty Velcro, paracord, and J-bead trim, which can be found at most hardware stores. It only costs a few dollars to treat windows. To learn more about installing these treatments, visit For more information about monitoring bird strikes, contact Dr. Mark Hostetler,


You can participate in collecting data and help find solutions on Birds and Window Strikes by using the app at  iNaturalist UF Bird Window Collision Project. This data is being used by the Florida Wildlife Extension and to provide tools for developers to design buildings that will help reduce the number of bird strikes.  Follow the link to read more details and how you can help.


Follow the links for more suggestions on how to prevent bird collisions:

Acopian BirdSavers

Wild Birds Unlimited

Stop Birds Hitting Windows

Glass Collision Solutions from the American Bird Conservancy